Self-aligning swinging drawbar



Oct. 12, 1948. L. ATKINSON SELF-ALIGNING SWINGING DRKWBAR 2 Sheets-Sheet 1 Filed June 18, 1946 game/MM AZ kinson Oct. 12, 1948. Nsg 2,451,054

SELF-ALIGNING SWINGING DRAWBAR Filed June 18, 194 2 Shets-Sheet 2 FIG-,5.

L. Aikinson Patented Oct. 12,. 1948 UNITED STATES PATENT 1 OFFICE l I r 2,451,054 vt ii SELF-ALIGNING SWINGING DRAWBAR Linwood Atkinson, Hillnian, Mich.

' Application June 18, 1946, Serial No. 677,55}

My invention pertains to an improvement in drawbars for tractors or other heavy vehicles used for heavy loads, and has for its object to give the proper line of draft when applied to such vehicle under all circumstances. All such drawbars formerly in'use are rigidly attached to the regular drawbar in such a manner as to give the proper line of draft horizontally only, whereas the present invention'provides for correct line of draft both horizontally and vertically.

For this purpose my invention uses a shock absorber on the swinging drawbar with arms attached by linkage to rollers guided on the regular drawbar, such swinging drawbar passing under said regular drawbar, which is raised, allowing freedom of action of the swinging drawbar. The latter will thus automatically find the correct line of draft. The swinging drawbar is provided with a spring on the under side of the rollers, whereby it becomfis raised to a higher position when not in use. The shock absorber has the function to hold the swinging drawbar steady, by retarding said drawbar in its vertical movement.

These and other objects and advantages will be made clear in the subjoined description aided by the attached drawing which forms part of this application.

..:In-the drawing, one embodiment of the invention is illustrated and shown.

Figure 1 is a perspective assembly view;

Figure 2 is a side view partly in section of some details in larger scale;

t Figure 3 is adiagrammatic view in side elevation;

Figure 4 is a sectional view taken on line 4-4 of Figure 3; and

Figure 5 is a section on line 5-5 of Figure 3.

Like reference numerals denote the same details in the difierent views of the drawing.

In the drawing, reference numeral l denotes the regular drawbar which is fixed on the axle ll of a tractor in the usual manner as by bars' l2 and braces l3. Behind the flat, transverse portion of the regular drawrbar I0 is secured in parallel relation thereto a track member I4 adapted to support the rollers l of a small trolley for running on said track I4 from end to end. From the trolley is suspended by links l6 a claw arm I! between the claws of which is pivoted a shock absorber of anysuitable kind, here diagrammatically shown at IS.

A suitable type of shockabsorber is the double acting Delco absorber which retards the motion of the swinging drawbar I9 in its vertical action.

10 Claims. ((11. 2803 3.44-)

The'shock absorber i8 is secured on top of the swinging bar l9 iby cap screws near its pulling end which is provided with an eye 2| for a draw pin. The other end of the swinging drawbar l9 extends forwardly beneath the regular drawbar Ill sufliciently to permit the pivotal attachment of itsu'pwardly bent end 22 to the axle H. The" swinging-bar I 9 is yieldingly supported by a spring 24 from the rear end of the arm l1. In order to limit the motion 'of the swinging drawbar I9 a bracket 25 is welded beneath the track member i i to provide a rectangularspace therewith to permit said bar with a vertical lift of about-six inclhes in said space and a horizontal swing between the ends of the track. Thus the trolley rollers 15 Will also be prevented from running oi the tr'ack and the shock absonber l8 to be" protected from injury from obstructing objects on the ground. It is to lee-understood that the invention as herein-disclosed-may be varied from the detai described and shownwithout departure from t spirit of the subjoinedclaims.

Iclaimi V 'lifA-tractor hitchwith self-adjusting drawbar in' combination with a stationary transverse drawbar member, comprising a track member secured parallel to and substantially level with said. stationary drawbar, an auxiliary drawbar pi.v' oted at one end of the tractor for limited hori zontal and vertical swinging movement and 6X tending beyond said stationary drawbar beneath the same, a runner element on-the track, a shock absorber secured on 'the'auxiliary drawbar adjac'ent to said track to move horizontally with the auxiliary drawbar, and a coupling between the runner element and the shock absorber whereby the shock absorber is made to function upon vertical swinging movement of the auxiliary drawbar.

2. A tractor hitch as described in claim 1, with a bracket beneath said track, forming a rectansaid track, forming a rectangular space beneathff the same for said auxiliary bar, a trolley on said track and arm and link connection between said trolley and said shock absorber, and a spring .said

normally sustaining the weight of said auxiliary bar on said arm.

5. A tractor hitch as described in claim 1, in which said means consist of a bracket beneath said track, forming a rectangular space beneath the same for said auxiliary bar, a trolley on said track and arm and link connection between said trolley and said shock absorber, said trolley being provided with rollers for running on said track.

6. A tractor hitch as described in claim 1, in which saidmeans' consist of a bracket beneath said track, forming a rectangular space beneath the same for said auxiliary bar, a trolley on said track and arm and link connection between said trolley and said shock absorber, sai'd 'trolleyb'eing provided with rollers for running on said track, and a spring normally sustaining the weight of said auxiliary bar onsaid'arm;

7. A tractor hitch with self-adjustingdrawbar in combination with a stationary transverse drawbar member, comprising a track member s ecl if edlparallel to and substantially level with saidi stationa ry drawbar, anauxiliary drawbar pivotedat 'oneend to the: tractor and extending beyond said stationary drawbar beneath the sam;.:terminatingwith a draw pin eye; a shock absorber secured on therauxiliary drawbar ad jacent isaid track and means permitting limited horizontal and vertical swinging of the auxiliary drawbar from its pivoted end, said means consisting- .of a bracket beneath said track, forming airectangular space beneath the same for said auxiliary-bar; 'a' trolley on said track and arm and-link connection between said trolley and said-shock absorber. V V

8., -Artractor bitch with self-adjusting drawbar in; combination with a stationary transverse drawbar-member,comprising a' track member secured parallel to and substantially level with said stationary drawbar, an auxiliary drawbar pivoted at, one end to the tractor and extending beyond\ tsaid stationary drawbar beneath the same, terminating with a draw pin eye; a shock absorber secured on the auxiliary drawbar adjacent said track and means permitting limited horizontal and vertical swinging of the auxiliary drawbar from its pivoted; end, said means consistingoi a bracket beneath said track, forming a rectangular sDace'beneath-the same for said auxiliary bar, a trolley on;sa id track-and arm and link connection between said trolley and saidshQck f absorber, anda spring, normall sustaining the weight of said auxiliary bar on said arm.

9, A tractor hitch with self-adjusting drawbar in combination with a stationary transverse drawbar member, comprising a track member secured parallel to and substantially level with said stationary drawbar, an auxiliary drawibar pivoted at one end to the tractor and extending beyond said stationary drawbar beneath the same, terminating with a draw pin eye; a shock absorber secured on the auxiliary drawbar adjacent said track and means permitting limited horizontal andvertical'swinging'" of the auxiliary a drawbar from its pivoted end; said means consisting of a bracket beneath said track, forming a rectangular space beneath the same for said auxiliary bar,'a.tro11ey on said track and arm and link connection between said trolley and said shock absorber, said trolley bein provided with rollers for running on said track.

10. A tractor hitch with self-adjusting draw- Ibar incc'ombination with a stationary transverse drawbar member, comprising a track member secured parallel i to and substantially t level With said: st onary draw any 12 5 drawbar. ri et d a w e ow t a n e tend beyond said stationary drawbar.beneath ab or r; se r 9 ih u i iar dr b r i jacent; said track and means permitting limited;

cri n lam e ical sw in cf th f uexi ar d awbar r l'a t p rQ dsnsi. sa d m wme sisting f ae c t e eath. a t ac firmin a re ta sul l ce:b eat hegsame sa x a y bar tro ley, ni aisi track a r with rol rsicrr nn -9o rzri e-inormal y su ain t e: au i ary n sa d em Number u C Iv 590,146. I Germany-2;: 

